Changes in lipid and phospholipid spectrum of blood serum in bacterial intestinal infections as predictors of irritable bowel syndrome development

Some patients develop irritable bowel syndrome (IBS) after acute diarrhea of bacterial etiology (ADBE). There are isolated works that present data concerning the parameters of total lipids and phospholipids in intestinal infections. The features of changes in lipid and phospholipid spectra in relation to the prognosis of IBS development in ADBE has not yet been evaluated. Objective. To evaluate serum lipid and phospholipid spectrum in patients with ADBE and to determine its significance in the development of IBS. Materials and methods. The study was performed in a group of patients with ADBE aged 18–65 years (n = 50) who received inpatient treatment in 2021–2022 at the Adygea Republican Infectious Diseases Hospital. For laboratory verification of the diagnosis, a bacteriological method and polymerase chain reaction (PCR) with a reagent kit “AmpliSens® AII screen-FL” were used. Blood sampling for lipid spectrum estimation was done on day 2–3 of the disease. The levels of triglycerides (TG), total cholesterol, high-density lipoproteins (HDL) and low-density lipoproteins (LDL), apolipoprotein A1 (APO-A1) and apolipoprotein-B (APO-B) were determined by enzymatic colorimetric method. Serum phospholipids were also isolated and fractionated into lysophosphatidylcholine, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine by a unified thin-layer chromatography using Sorbfil TLC plates and Sorbfil TLC densitometer. SPSS Statistics 26.0 program was used to process the obtained results. ROC analysis was used to estimate the probability of IBS development. Results. The study of total lipid spectrum in patients in the acute period of the disease revealed hypertriglyceridemia of 2.2 mmol/L (95% CI: 1.9–2.5), which was observed in 62% of patients. An increase in the level of phosphatidylcholine was observed in 90% of patients, lysophosphatidylcholine – in 56%, a decrease in the level of phosphatidylethanolamine – in 72%, and sphingomyelin – in 24%. Subsequently, within a month after convalescence, 16 (32%) patients developed IBS. For the parameters that were altered in most patients with IBS (cholesterol, TG, phosphatidylcholine, phosphatidylethanolamine), ROC analysis was performed to assess the risk of developing post-infectious IBS. At a cholesterol level of 3.75 mmol/L and higher (AUC = 0.716 ± 0.086; p = 0.019), blood triglycerides 2.115 mmol/L and higher (AUC = 0.889 ± 0.051; p < 0.001), phosphatidylcholine 63.8% and higher (AUC = 0.827 ± 0.058; p < 0.001), phosphatidylethanolamine 14.3% and lower (AUC = 0.853 ± 0.055; p < 0.001), a high risk of developing IBS was predicted. Conclusion. Based on the increase in the level of cholesterol, triglycerides, phosphatidylcholine above or decrease in the level of phosphatidylethanolamine below the threshold values obtained by ROC analysis, it is possible to predict a high or low risk of IBS development in ADBE patients and to determine indications for timely preventive therapy of this pathology. Key words: cholesterol, triglycerides, lipids, bacterial intestinal infections, irritable bowel syndrome